1. Field
The following description relates to providing a user interface using an acoustic signal, for example, a surface acoustic signal.
2. Description of Related Art
Apparatuses for providing a user interface to operate an electronic device to perform functions have been developed mainly in the form of an operation key, a button, a mouse, or a touch screen. Since conventional user interface providing apparatuses typically include an electronic circuit employing a device such as a button and a screen, there is therefore a limited area in which a user may input a command. In other words, there is a limit in that an area in which such an input device of the electronic circuit is not installed cannot be used as an interface, i.e., cannot be used as an input range. Also, when an interface apparatus is built in a curved area, rather than a flat surface, and in a general object such as a piece of furniture or a wall, the user interface needs to be durable against impacts and contaminants. Such qualities are, however, difficult to achieve.
The conventional user interface providing apparatuses operate in the state of being fixed to a predetermined region of the electronic device. To this end, if an interface of the electronic device, that is, the input range, is disposed in a location difficult for a user to reach, such as inside of clothes or a bag, the interface becomes inconvenient to operate. In particular, when the electronic device has a limited amount of space, for example, as in a mobile device, it is difficult to secure sufficient input space.
Accordingly, there is a desire for an interfacing technology capable of overcoming the limit of the input space of the interface and reducing the cost in comparison with conventional interface devices.